Rice bran is a byproduct of the rice milling process (the conversion of brown rice to white rice), and it contains various antioxidants that impart beneficial effects on human health.A major rice bran fraction contains 12%-13% oil and highly unsaponifiable components (4.3%).This fraction contains tocotrienols (a form ofvitamin E), gamma-oryzanol and beta-sitosterol; all these constituents may contribute to the lowering of the plasma levels of the various parameters of the lipid profile. Rice bran also contains a high level of dietary fibres (beta-glucan, pectin and gum). In addition, it also contains ferulic acid, which is also a component of the structure of nonlignified cell walls. However, some research suggests there are levels of inorganic arsenic (a toxin and carcinogen) present in rice bran. One study found the levels to be 20% higher than in drinking water.Other types of bran (derived from wheat, oat or barley) contain less arsenic than rice bran, and are nutrient-rich.